1. Field of the Invention
The present invention relates to an ink tank comprising a casing having a front wall formed with a coupling, and a bag disposed in the casing and connected to the coupling.
2. Background Art
Several ink jet printers comprise an ink tank that has a comparatively large volume and is arranged to be stationary in the frame of the printer and is connected to a movable ink jet device through a flexible tube. In operation, ink supply to the ink jet device is achieved either by drawing ink out of the tank or by supplying air into the space inside of the casing but outside of the bag, so that the bag can be collapsed and the ink can be squeezed out. The supply of ink from the tank to the ink jet device may be assisted by gravitational forces. As an alternative, ink supply might be achieved through gravitational forces alone, provided that the casing can be vented. In any case, the bag prevents the ink from leaking out of the casing and/or from being dried out through contact with the air in the casing, whereas the casing prevents the bag from being damaged or squeezed and facilitates the handling of the ink tank. An example of an ink tank of this type is described in U.S. Pat. No. 6,264,318.